Castro Juan M, Bianchi Virginia A, Felici Emiliano, De Anna Julieta S, Venturino Andrés, Luquet Carlos M
Laboratorio de Ecotoxicología Acuática, Subsede Instituto de Investigaciones en Biodiversidad y Medioambiente-Consejo Nacional de Investigaciones Científicas y Técnicas-Universidad Nacional del Comahue, Junín de los Andes, Neuquén, Argentina.
Instituto de Química de San Luis, Departamento de Farmacia, Facultad de Química, Bioquímica y Farmacia, Universidad Nacional de San Luis, San Luis, Argentina.
Environ Toxicol Chem. 2023 Jan;42(1):154-165. doi: 10.1002/etc.5507. Epub 2022 Dec 7.
Copper is a water and sediment pollutant that can be biomagnified by phytoplankton, and it often co-occurs with fecal bacteria. We addressed the combined effects of copper and Escherichia coli on the immune response and gill oxidative balance of the freshwater mussel Diplodon chilensis. Bivalves were sorted into four groups fed with 1) control algae, 2) bacteria (E. coli), 3) copper-enriched algae (Cu ) algae, and 4) copper-enriched algae followed by bacteria (Cu + E. coli). Cellular and humoral immune and cytotoxic variables were analyzed in hemolymph, and detoxifying/antioxidant enzyme activities (glutathione S-transferase [GST] and catalase [CAT]) and lipid peroxidation (thiobarbituric acid reactive substances [TBARS]) were studied in gill tissue. The total hemocyte number increased after Cu exposure, independently of the E. coli challenge. The proportion of hyalinocytes significantly diminished in the E. coli and Cu groups but not in Cu + E. coli groups; granulocytes significantly increased with E. coli but not with Cu + E. coli treatments. Phagocytic activity was higher in all treatments than in control mussels. Acid phosphatase activity was increased by E. coli and inhibited by Cu and Cu + E. coli. Both E. coli and Cu but not Cu + E. coli augmented alkaline phosphatase activity. The Cu and Cu + E. coli treatments reduced the lysosomal membrane stability and cell viability. Humoral bacteriolytic and phenol oxidase activities were not affected by any treatment. The Cu treatment induced gill CAT and GST activities and increased TBARS levels. The Cu + E. coli treatment reversed this CAT and GST stimulation and increased the Cu effect on TBARS. Dietary Cu affects bivalves' immunological and oxidative status and impairs defensive responses against bacteria. In turn, E. coli potentiates the gill oxidative effects of Cu . Environ Toxicol Chem 2023;42:154-165. © 2022 SETAC.
铜是一种水和沉积物污染物，可被浮游植物生物放大，并且它经常与粪便细菌同时出现。我们研究了铜和大肠杆菌对淡水贻贝智利双齿蚌免疫反应和鳃氧化平衡的联合影响。双壳贝类被分为四组，分别投喂1) 对照藻类，2) 细菌（大肠杆菌），3) 富含铜的藻类（Cu）藻类，以及4) 先投喂富含铜的藻类然后投喂细菌（Cu + 大肠杆菌）。分析了血淋巴中的细胞和体液免疫及细胞毒性变量，并研究了鳃组织中的解毒/抗氧化酶活性（谷胱甘肽S-转移酶 [GST] 和过氧化氢酶 [CAT]）以及脂质过氧化（硫代巴比妥酸反应性物质 [TBARS]）。暴露于铜后，总血细胞数增加，与大肠杆菌攻击无关。在大肠杆菌组和铜组中，透明细胞的比例显著降低，但在铜 + 大肠杆菌组中没有；粒细胞在大肠杆菌处理后显著增加，但在铜 + 大肠杆菌处理后没有。所有处理组的吞噬活性均高于对照贻贝。酸性磷酸酶活性被大肠杆菌增加，而被铜和铜 + 大肠杆菌抑制。大肠杆菌和铜都增加了碱性磷酸酶活性，但铜 + 大肠杆菌没有。铜和铜 + 大肠杆菌处理降低了溶酶体膜稳定性和细胞活力。体液溶菌和酚氧化酶活性不受任何处理的影响。铜处理诱导了鳃CAT和GST活性，并增加了TBARS水平。铜 + 大肠杆菌处理逆转了这种CAT和GST刺激，并增强了铜对TBARS的影响。膳食铜会影响双壳贝类的免疫和氧化状态，并损害其对细菌的防御反应。反过来，大肠杆菌会增强铜对鳃的氧化作用。《环境毒理学与化学》2023年；42:154 - 165。© 2022 SETAC。
